diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/staging/greybus/gpio.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/staging/greybus/gpio.c')
-rw-r--r-- | drivers/staging/greybus/gpio.c | 630 |
1 files changed, 630 insertions, 0 deletions
diff --git a/drivers/staging/greybus/gpio.c b/drivers/staging/greybus/gpio.c new file mode 100644 index 000000000..7e6347fe9 --- /dev/null +++ b/drivers/staging/greybus/gpio.c @@ -0,0 +1,630 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GPIO Greybus driver. + * + * Copyright 2014 Google Inc. + * Copyright 2014 Linaro Ltd. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/gpio/driver.h> +#include <linux/mutex.h> +#include <linux/greybus.h> + +#include "gbphy.h" + +struct gb_gpio_line { + /* The following has to be an array of line_max entries */ + /* --> make them just a flags field */ + u8 active: 1, + direction: 1, /* 0 = output, 1 = input */ + value: 1; /* 0 = low, 1 = high */ + u16 debounce_usec; + + u8 irq_type; + bool irq_type_pending; + bool masked; + bool masked_pending; +}; + +struct gb_gpio_controller { + struct gbphy_device *gbphy_dev; + struct gb_connection *connection; + u8 line_max; /* max line number */ + struct gb_gpio_line *lines; + + struct gpio_chip chip; + struct irq_chip irqc; + struct mutex irq_lock; +}; +#define gpio_chip_to_gb_gpio_controller(chip) \ + container_of(chip, struct gb_gpio_controller, chip) +#define irq_data_to_gpio_chip(d) (d->domain->host_data) + +static int gb_gpio_line_count_operation(struct gb_gpio_controller *ggc) +{ + struct gb_gpio_line_count_response response; + int ret; + + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_LINE_COUNT, + NULL, 0, &response, sizeof(response)); + if (!ret) + ggc->line_max = response.count; + return ret; +} + +static int gb_gpio_activate_operation(struct gb_gpio_controller *ggc, u8 which) +{ + struct gb_gpio_activate_request request; + struct gbphy_device *gbphy_dev = ggc->gbphy_dev; + int ret; + + ret = gbphy_runtime_get_sync(gbphy_dev); + if (ret) + return ret; + + request.which = which; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_ACTIVATE, + &request, sizeof(request), NULL, 0); + if (ret) { + gbphy_runtime_put_autosuspend(gbphy_dev); + return ret; + } + + ggc->lines[which].active = true; + + return 0; +} + +static void gb_gpio_deactivate_operation(struct gb_gpio_controller *ggc, + u8 which) +{ + struct gbphy_device *gbphy_dev = ggc->gbphy_dev; + struct device *dev = &gbphy_dev->dev; + struct gb_gpio_deactivate_request request; + int ret; + + request.which = which; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DEACTIVATE, + &request, sizeof(request), NULL, 0); + if (ret) { + dev_err(dev, "failed to deactivate gpio %u\n", which); + goto out_pm_put; + } + + ggc->lines[which].active = false; + +out_pm_put: + gbphy_runtime_put_autosuspend(gbphy_dev); +} + +static int gb_gpio_get_direction_operation(struct gb_gpio_controller *ggc, + u8 which) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_get_direction_request request; + struct gb_gpio_get_direction_response response; + int ret; + u8 direction; + + request.which = which; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_GET_DIRECTION, + &request, sizeof(request), + &response, sizeof(response)); + if (ret) + return ret; + + direction = response.direction; + if (direction && direction != 1) { + dev_warn(dev, "gpio %u direction was %u (should be 0 or 1)\n", + which, direction); + } + ggc->lines[which].direction = direction ? 1 : 0; + return 0; +} + +static int gb_gpio_direction_in_operation(struct gb_gpio_controller *ggc, + u8 which) +{ + struct gb_gpio_direction_in_request request; + int ret; + + request.which = which; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DIRECTION_IN, + &request, sizeof(request), NULL, 0); + if (!ret) + ggc->lines[which].direction = 1; + return ret; +} + +static int gb_gpio_direction_out_operation(struct gb_gpio_controller *ggc, + u8 which, bool value_high) +{ + struct gb_gpio_direction_out_request request; + int ret; + + request.which = which; + request.value = value_high ? 1 : 0; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DIRECTION_OUT, + &request, sizeof(request), NULL, 0); + if (!ret) + ggc->lines[which].direction = 0; + return ret; +} + +static int gb_gpio_get_value_operation(struct gb_gpio_controller *ggc, + u8 which) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_get_value_request request; + struct gb_gpio_get_value_response response; + int ret; + u8 value; + + request.which = which; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_GET_VALUE, + &request, sizeof(request), + &response, sizeof(response)); + if (ret) { + dev_err(dev, "failed to get value of gpio %u\n", which); + return ret; + } + + value = response.value; + if (value && value != 1) { + dev_warn(dev, "gpio %u value was %u (should be 0 or 1)\n", + which, value); + } + ggc->lines[which].value = value ? 1 : 0; + return 0; +} + +static void gb_gpio_set_value_operation(struct gb_gpio_controller *ggc, + u8 which, bool value_high) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_set_value_request request; + int ret; + + if (ggc->lines[which].direction == 1) { + dev_warn(dev, "refusing to set value of input gpio %u\n", + which); + return; + } + + request.which = which; + request.value = value_high ? 1 : 0; + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_SET_VALUE, + &request, sizeof(request), NULL, 0); + if (ret) { + dev_err(dev, "failed to set value of gpio %u\n", which); + return; + } + + ggc->lines[which].value = request.value; +} + +static int gb_gpio_set_debounce_operation(struct gb_gpio_controller *ggc, + u8 which, u16 debounce_usec) +{ + struct gb_gpio_set_debounce_request request; + int ret; + + request.which = which; + request.usec = cpu_to_le16(debounce_usec); + ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_SET_DEBOUNCE, + &request, sizeof(request), NULL, 0); + if (!ret) + ggc->lines[which].debounce_usec = debounce_usec; + return ret; +} + +static void _gb_gpio_irq_mask(struct gb_gpio_controller *ggc, u8 hwirq) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_irq_mask_request request; + int ret; + + request.which = hwirq; + ret = gb_operation_sync(ggc->connection, + GB_GPIO_TYPE_IRQ_MASK, + &request, sizeof(request), NULL, 0); + if (ret) + dev_err(dev, "failed to mask irq: %d\n", ret); +} + +static void _gb_gpio_irq_unmask(struct gb_gpio_controller *ggc, u8 hwirq) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_irq_unmask_request request; + int ret; + + request.which = hwirq; + ret = gb_operation_sync(ggc->connection, + GB_GPIO_TYPE_IRQ_UNMASK, + &request, sizeof(request), NULL, 0); + if (ret) + dev_err(dev, "failed to unmask irq: %d\n", ret); +} + +static void _gb_gpio_irq_set_type(struct gb_gpio_controller *ggc, + u8 hwirq, u8 type) +{ + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_gpio_irq_type_request request; + int ret; + + request.which = hwirq; + request.type = type; + + ret = gb_operation_sync(ggc->connection, + GB_GPIO_TYPE_IRQ_TYPE, + &request, sizeof(request), NULL, 0); + if (ret) + dev_err(dev, "failed to set irq type: %d\n", ret); +} + +static void gb_gpio_irq_mask(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_to_gpio_chip(d); + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + struct gb_gpio_line *line = &ggc->lines[d->hwirq]; + + line->masked = true; + line->masked_pending = true; +} + +static void gb_gpio_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_to_gpio_chip(d); + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + struct gb_gpio_line *line = &ggc->lines[d->hwirq]; + + line->masked = false; + line->masked_pending = true; +} + +static int gb_gpio_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *chip = irq_data_to_gpio_chip(d); + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + struct gb_gpio_line *line = &ggc->lines[d->hwirq]; + struct device *dev = &ggc->gbphy_dev->dev; + u8 irq_type; + + switch (type) { + case IRQ_TYPE_NONE: + irq_type = GB_GPIO_IRQ_TYPE_NONE; + break; + case IRQ_TYPE_EDGE_RISING: + irq_type = GB_GPIO_IRQ_TYPE_EDGE_RISING; + break; + case IRQ_TYPE_EDGE_FALLING: + irq_type = GB_GPIO_IRQ_TYPE_EDGE_FALLING; + break; + case IRQ_TYPE_EDGE_BOTH: + irq_type = GB_GPIO_IRQ_TYPE_EDGE_BOTH; + break; + case IRQ_TYPE_LEVEL_LOW: + irq_type = GB_GPIO_IRQ_TYPE_LEVEL_LOW; + break; + case IRQ_TYPE_LEVEL_HIGH: + irq_type = GB_GPIO_IRQ_TYPE_LEVEL_HIGH; + break; + default: + dev_err(dev, "unsupported irq type: %u\n", type); + return -EINVAL; + } + + line->irq_type = irq_type; + line->irq_type_pending = true; + + return 0; +} + +static void gb_gpio_irq_bus_lock(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_to_gpio_chip(d); + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + mutex_lock(&ggc->irq_lock); +} + +static void gb_gpio_irq_bus_sync_unlock(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_to_gpio_chip(d); + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + struct gb_gpio_line *line = &ggc->lines[d->hwirq]; + + if (line->irq_type_pending) { + _gb_gpio_irq_set_type(ggc, d->hwirq, line->irq_type); + line->irq_type_pending = false; + } + + if (line->masked_pending) { + if (line->masked) + _gb_gpio_irq_mask(ggc, d->hwirq); + else + _gb_gpio_irq_unmask(ggc, d->hwirq); + line->masked_pending = false; + } + + mutex_unlock(&ggc->irq_lock); +} + +static int gb_gpio_request_handler(struct gb_operation *op) +{ + struct gb_connection *connection = op->connection; + struct gb_gpio_controller *ggc = gb_connection_get_data(connection); + struct device *dev = &ggc->gbphy_dev->dev; + struct gb_message *request; + struct gb_gpio_irq_event_request *event; + u8 type = op->type; + int irq, ret; + + if (type != GB_GPIO_TYPE_IRQ_EVENT) { + dev_err(dev, "unsupported unsolicited request: %u\n", type); + return -EINVAL; + } + + request = op->request; + + if (request->payload_size < sizeof(*event)) { + dev_err(dev, "short event received (%zu < %zu)\n", + request->payload_size, sizeof(*event)); + return -EINVAL; + } + + event = request->payload; + if (event->which > ggc->line_max) { + dev_err(dev, "invalid hw irq: %d\n", event->which); + return -EINVAL; + } + + irq = irq_find_mapping(ggc->chip.irq.domain, event->which); + if (!irq) { + dev_err(dev, "failed to find IRQ\n"); + return -EINVAL; + } + + local_irq_disable(); + ret = generic_handle_irq(irq); + local_irq_enable(); + + if (ret) + dev_err(dev, "failed to invoke irq handler\n"); + + return ret; +} + +static int gb_gpio_request(struct gpio_chip *chip, unsigned int offset) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + return gb_gpio_activate_operation(ggc, (u8)offset); +} + +static void gb_gpio_free(struct gpio_chip *chip, unsigned int offset) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + gb_gpio_deactivate_operation(ggc, (u8)offset); +} + +static int gb_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + u8 which; + int ret; + + which = (u8)offset; + ret = gb_gpio_get_direction_operation(ggc, which); + if (ret) + return ret; + + return ggc->lines[which].direction ? 1 : 0; +} + +static int gb_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + return gb_gpio_direction_in_operation(ggc, (u8)offset); +} + +static int gb_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + return gb_gpio_direction_out_operation(ggc, (u8)offset, !!value); +} + +static int gb_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + u8 which; + int ret; + + which = (u8)offset; + ret = gb_gpio_get_value_operation(ggc, which); + if (ret) + return ret; + + return ggc->lines[which].value; +} + +static void gb_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + + gb_gpio_set_value_operation(ggc, (u8)offset, !!value); +} + +static int gb_gpio_set_config(struct gpio_chip *chip, unsigned int offset, + unsigned long config) +{ + struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); + u32 debounce; + + if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE) + return -ENOTSUPP; + + debounce = pinconf_to_config_argument(config); + if (debounce > U16_MAX) + return -EINVAL; + + return gb_gpio_set_debounce_operation(ggc, (u8)offset, (u16)debounce); +} + +static int gb_gpio_controller_setup(struct gb_gpio_controller *ggc) +{ + int ret; + + /* Now find out how many lines there are */ + ret = gb_gpio_line_count_operation(ggc); + if (ret) + return ret; + + ggc->lines = kcalloc(ggc->line_max + 1, sizeof(*ggc->lines), + GFP_KERNEL); + if (!ggc->lines) + return -ENOMEM; + + return ret; +} + +static int gb_gpio_probe(struct gbphy_device *gbphy_dev, + const struct gbphy_device_id *id) +{ + struct gb_connection *connection; + struct gb_gpio_controller *ggc; + struct gpio_chip *gpio; + struct gpio_irq_chip *girq; + struct irq_chip *irqc; + int ret; + + ggc = kzalloc(sizeof(*ggc), GFP_KERNEL); + if (!ggc) + return -ENOMEM; + + connection = + gb_connection_create(gbphy_dev->bundle, + le16_to_cpu(gbphy_dev->cport_desc->id), + gb_gpio_request_handler); + if (IS_ERR(connection)) { + ret = PTR_ERR(connection); + goto exit_ggc_free; + } + + ggc->connection = connection; + gb_connection_set_data(connection, ggc); + ggc->gbphy_dev = gbphy_dev; + gb_gbphy_set_data(gbphy_dev, ggc); + + ret = gb_connection_enable_tx(connection); + if (ret) + goto exit_connection_destroy; + + ret = gb_gpio_controller_setup(ggc); + if (ret) + goto exit_connection_disable; + + irqc = &ggc->irqc; + irqc->irq_mask = gb_gpio_irq_mask; + irqc->irq_unmask = gb_gpio_irq_unmask; + irqc->irq_set_type = gb_gpio_irq_set_type; + irqc->irq_bus_lock = gb_gpio_irq_bus_lock; + irqc->irq_bus_sync_unlock = gb_gpio_irq_bus_sync_unlock; + irqc->name = "greybus_gpio"; + + mutex_init(&ggc->irq_lock); + + gpio = &ggc->chip; + + gpio->label = "greybus_gpio"; + gpio->parent = &gbphy_dev->dev; + gpio->owner = THIS_MODULE; + + gpio->request = gb_gpio_request; + gpio->free = gb_gpio_free; + gpio->get_direction = gb_gpio_get_direction; + gpio->direction_input = gb_gpio_direction_input; + gpio->direction_output = gb_gpio_direction_output; + gpio->get = gb_gpio_get; + gpio->set = gb_gpio_set; + gpio->set_config = gb_gpio_set_config; + gpio->base = -1; /* Allocate base dynamically */ + gpio->ngpio = ggc->line_max + 1; + gpio->can_sleep = true; + + girq = &gpio->irq; + girq->chip = irqc; + /* The event comes from the outside so no parent handler */ + girq->parent_handler = NULL; + girq->num_parents = 0; + girq->parents = NULL; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_level_irq; + + ret = gb_connection_enable(connection); + if (ret) + goto exit_line_free; + + ret = gpiochip_add(gpio); + if (ret) { + dev_err(&gbphy_dev->dev, "failed to add gpio chip: %d\n", ret); + goto exit_line_free; + } + + gbphy_runtime_put_autosuspend(gbphy_dev); + return 0; + +exit_line_free: + kfree(ggc->lines); +exit_connection_disable: + gb_connection_disable(connection); +exit_connection_destroy: + gb_connection_destroy(connection); +exit_ggc_free: + kfree(ggc); + return ret; +} + +static void gb_gpio_remove(struct gbphy_device *gbphy_dev) +{ + struct gb_gpio_controller *ggc = gb_gbphy_get_data(gbphy_dev); + struct gb_connection *connection = ggc->connection; + int ret; + + ret = gbphy_runtime_get_sync(gbphy_dev); + if (ret) + gbphy_runtime_get_noresume(gbphy_dev); + + gb_connection_disable_rx(connection); + gpiochip_remove(&ggc->chip); + gb_connection_disable(connection); + gb_connection_destroy(connection); + kfree(ggc->lines); + kfree(ggc); +} + +static const struct gbphy_device_id gb_gpio_id_table[] = { + { GBPHY_PROTOCOL(GREYBUS_PROTOCOL_GPIO) }, + { }, +}; +MODULE_DEVICE_TABLE(gbphy, gb_gpio_id_table); + +static struct gbphy_driver gpio_driver = { + .name = "gpio", + .probe = gb_gpio_probe, + .remove = gb_gpio_remove, + .id_table = gb_gpio_id_table, +}; + +module_gbphy_driver(gpio_driver); +MODULE_LICENSE("GPL v2"); |